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    <title>Document</title>
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<body>
    <script>
        // 根据位置返回字符
        // 1.charAt(index) 根据索引号返回字符
        let str = "abcdef"
        console.log(str.charAt);

        // 2. str[index] H5 新增的
        console.log(str[0]);

        // 3.charCodeAt(index) 返回相应索引号的字符 ASCII值 目的：判断用户按下了哪个键
        console.log(str.charCodeAt(0));

        // 4.ASCII码值转换为对应字符、
        let result = String.fromCharCode(65);
        console.log(result);

        let arr = [];
        for (let i = 65; i < 91; i++) {
            let temp = String.fromCharCode(i);
            arr.push(temp);

        }
        console.log(arr);
    </script>
</body>

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